This research was funded by CRIS 5358-21000-011-000 at the U.S. Dept. of Agriculture, Agricultural Research Service, National Clonal Germplasm Repository, Corvallis, Ore. The cost of publishing
The research was funded by CRIS 5358-21000-011-000 at the U.S. Dept. of Agriculture, Agricultural Research Service, National Clonal Germplasm Repository, Corvallis, Ore. The cost of publishing this
, coconut wine, and other processed products or by-products favored and trusted by an increasing number of consumers ( Xia et al., 2007 ; Zhang, 2011 ). Therefore, researching coconut germplasm resources is of great importance.
The local coconut resources
field, as occurred in Florida in 1992–93 and in 2010. Therefore, efforts need to be made to screen additional cultivars and germplasm lines for new sources of resistance. Two types of experiments (field and greenhouse) have been used to evaluate lettuce
The research was conducted at the experiment station of the U.S. Department of Agriculture (USDA), Salinas, CA. The spinach collection (332 accessions) from the National Plant Germplasm System, USDA [North Central Regional Plant Introduction (PI
al., 2008 ). Heat tolerance is a complex trait that varies with the severity of stress and plant growth stage. Therefore, there is a need to identify heat-tolerant carrot germplasm with stable growth and yield under high temperature at various stages
St. Augustinegrass [Stenotaphrum secundatum (Walt.) Kuntze] is less drought-resistant than other C4 grasses and frequently requires irrigation in lawns. The objectives of this study were to search for St. Augustinegrass germplasm having little wilting and to determine if minimal wilting under drought is associated with reduced canopy loss. St. Augustinegrass cultivars and breeding lines, representing polyploids (2n = 27 to 32) and diploids (2n = 18), were grown in sand soil and exposed to irrigation suspensions during seasonal droughts in three experiments. In the first experiment, during brief (3 to 14 day) irrigation suspensions, wilted area over 3 years was significantly less for polyploids (6% of canopy) than for diploids (23%). In the second experiment, during a permanent irrigation suspension, frequency of wilt was highest for diploids (57%), least for African polyploids (27%), and intermediate (53%) for other polyploids. When rain resumed after 41 days of drought, allowing refoliation, canopy loss was 51%, 4%, and 47% for diploids, African polyploids, and other polyploids, respectively. In the third experiment, during a permanent irrigation suspension, wilted area was 33% for `Jade,' a diploid, which was more (P ≤ 0.05) than for the polyploid `FX-10,' with a wilted area of 20%. `Floratam' and `Bitterblue' were intermediate in wilted area, 28% and 25%, respectively. When rain resumed after 18 days of drought, canopy loss was 58% and 56% for `Jade' and `Bitterblue,' respectively, which was more than for `Floratam' and `FX-10,' 11% and 6%. Following permanent irrigation suspensions, canopy loss was closely associated with wilting, r2 = 0.88 and 0.94 by the Gompertz nonlinear model. Because the sand soil had low water-holding capacity, the wet subsoil and shallow (1.35 m deep) water table may have been a source of water. Wilt-avoidant St. Augustinegrass may help reduce turfgrass water use.
Gray.’ Mortality was highest for PI 537277 (37%) and PI 346082 (35%) and lowest for ‘Calhoun Gray’ (13%). Table 3. Incidence of adults, egg deposition, and adult mortality of B. tabaci on Citrullus germplasm in 24 h no choice vertical monitoring